Use of cannabinoids in the treatment of epilepsy

ABSTRACT

The present disclosure relates to the use of cannabidiol (CBD) for the reduction of total convulsive seizure frequency in the treatment of “treatment-resistant epilepsy” (TRE). In particular, the disclosure relates to the use of CBD of treating TRE when the TRE is Dravet syndrome; myoclonic absence seizures or febrile infection related epilepsy syndrome (FIRES). The disclosure further relates to the use of CBD in combination with one or more anti-epileptic drugs (AEDs).

This application is a continuation of Ser. No. 15/284,766, filed Oct. 4,2016, which is a continuation of Ser. No. 14/741,783 filed Jun. 17,2015, which claims the benefit of priority of GB 1506550.1, filed Apr.17, 2015, and GB 1410771.8, filed Jun. 17, 2014, each of which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to the use of cannabidiol (CBD) for thereduction of total convulsive seizure frequency in the treatment of“treatment-resistant epilepsy” (TRE). In one embodiment the patientssuffering from TRE are children and young adults. CBD appearsparticularly effective when the TRE is Dravet syndrome; myoclonicabsence seizures or febrile infection related epilepsy syndrome (FIRES).In these indications the reduction of total convulsive frequency hassurprisingly been shown to be greater than 50%, through 70% to greaterthan 90% in a significant number of patients. Indeed a significantnumber of patients have been seizure free at the end of three monthstreatment.

Preferably the CBD used is in the form of a highly purified extract ofcannabis such that the CBD is present at greater than 98% of the totalextract (w/w) and the other components of the extract are characterised.In particular tetrahydrocannabinol (THC) has been substantially removedto a level of not more than 0.15% (w/w). Alternatively, it is asynthetically produced CBD.

In use the CBD is used concomitantly with one or more otheranti-epileptic drugs (AED). Alternatively the CBD may be formulated foradministration separately, sequentially or simultaneously with one ormore AED or the combination may be provided in a single dosage form.Where the CBD is formulated for administration separately, sequentiallyor simultaneously it may be provided as a kit or together withinstructions to administer the one or more components in the mannerindicated.

BACKGROUND TO THE INVENTION

Epilepsy occurs in approximately 1% of the population worldwide,(Thurman et al., 2011) of which 70% are able to adequately control theirsymptoms with the available existing anti-epileptic drugs (AED).However, 30% of this patient group, (Eadie et al., 2012), are unable toobtain seizure freedom from the AED that are available and as such aretermed as suffering from “treatment-resistant epilepsy” (TRE).

Treatment-resistant epilepsy was defined in 2009 by the InternationalLeague Against Epilepsy (ILAE) as “failure of adequate trials of twotolerated and appropriately chosen and used AED schedules (whether asmonotherapies or in combination) to achieve sustained seizure freedom”(Kwan et al., 2009).

Individuals who develop epilepsy during the first few years of life areoften difficult to treat and as such are often termedtreatment-resistant. Children who undergo frequent seizures in childhoodare often left with neurological damage which can cause cognitive,behavioral and motor delays.

Childhood epilepsy is a relatively common neurological disorder inchildren and young adults with a prevalence of approximately 700 per100,000. This is twice the number of epileptic adults per population.

When a child or young adult presents with a seizure, investigations arenormally undertaken in order to investigate the cause. Childhoodepilepsy can be caused by many different syndromes and genetic mutationsand as such diagnosis for these children may take some time.

One such childhood epilepsy is Dravet syndrome. Onset of Dravet syndromealmost always occurs during the first year of life with clonic andtonic-clonic seizures in previously healthy and developmentally normalinfants (Dravet, 2011). Symptoms peak at about five months of age. Otherseizures develop between one and four years of age such as prolongedfocal dyscognitive seizures and brief absence seizures.

Seizures progress to be frequent and treatment-resistant, meaning thatthe seizures do not respond well to treatment. They also tend to beprolonged, lasting more than 5 minutes. Prolonged seizures may lead tostatus epilepticus, which is a seizure that lasts more than 30 minutes,or seizures that occur in clusters, one after another.

Prognosis is poor and approximately 14% of children die during aseizure, because of infection, or suddenly due to uncertain causes,often because of the relentless neurological decline. Patients developintellectual disability and life-long ongoing seizures. Intellectualimpairment varies from severe in 50% patients, to moderate and mildintellectual disability each accounting for 25% of cases.

There are currently no FDA approved treatments specifically indicatedfor Dravet syndrome. The standard of care usually involves a combinationof the following anticonvulsants: clobazam, clonazepam, levetiracetam,topiramate and valproic acid.

Stiripentol is approved in Europe for the treatment of Dravet syndromein conjunction with clobazam and valproic acid. In the US, stiripentolwas granted an Orphan Designation for the treatment of Dravet syndromein 2008; however, the drug is not FDA approved.

Potent sodium channel blockers used to treat epilepsy actually increaseseizure frequency in patients with Dravet Syndrome. The most common arephenytoin, carbamazepine, lamotrigine and rufinamide.

Management may also include a ketogenic diet, and physical and vagusnerve stimulation. In addition to anti-convulsive drugs, many patientswith Dravet syndrome are treated with anti-psychotic drugs, stimulants,and drugs to treat insomnia.

Common AED defined by their mechanisms of action are described in thefollowing tables:

Examples of Narrow Spectrum AED

Narrow-spectrum AED Mechanism Phenytoin Sodium channel PhenobarbitalGABA/Calcium channel Carbamazepine Sodium channel Oxcarbazepine Sodiumchannel Gabapentin Calcium channel Pregabalin Calcium channel LacosamideSodium channel Vigabatrin GABA

Examples of Broad Spectrum AED

Broad-spectrum AED Mechanism Valproic acid GABA/Sodium channelLamotrigine Sodium channel Topiramate GABA/Sodium channel ZonisamideGABA/Calcium/Sodium channel Levetiracetam Calcium channel ClonazepamGABA Rufinamide Sodium channel

Examples of AED Used Specifically in Childhood Epilepsy

AED Mechanism Clobazam GABA Stiripentol GABA

Over the past forty years there have been a number of animal studies onthe use of the non-psychoactive cannabinoid cannabidiol (CBD) to treatseizures. For example, Consroe et al., (1982) determined that CBD wasable to prevent seizures in mice after administration of pro-convulsantdrugs or an electric current.

Studies in epileptic adults have also occurred in the past forty yearswith CBD. Cunha et al. reported that administration of CBD to eightadult patients with generalized epilepsy resulted in a marked reductionof seizures in 4 of the patients (Cunha et al., 1980).

A study in 1978 provided 200 mg/day of pure CBD to four adult patients,two of the four patients became seizure free, whereas in the remainderseizure frequency was unchanged (Mechoulam and Carlini, 1978).

In contrast to the studies described above, an open label study reportedthat 200 mg/day of pure CBD was ineffective in controlling seizures intwelve institutionalized adult patients (Ames and Cridland, 1986).

Based on the fact that chronologically the last study to look at theeffectiveness of CBD in patients with epilepsy proved that CBD wasunable to control seizures, there would be no expectation that CBD mightbe useful as an anti-convulsant agent.

In the past forty years of research there have been over thirty drugsapproved for the treatment of epilepsy none of which are cannabinoids.Indeed, there appears to have been a prejudice against cannabinoids,possible due to the scheduled nature of these compounds and/or the factthat THC, which is a known psychoactive, has been ascribed as apro-convulsant (Consroe et al., 1977).

A paper published recently suggested that cannabidiol-enriched cannabismay be efficacious in the treatment of epilepsy. Porter and Jacobson(2013) report on a parent survey conducted via a Facebook group whichexplored the use of cannabis which was enriched with CBD in childrenwith treatment-resistant epilepsy. It was found that sixteen of the 19parents surveyed reported an improvement in their child's epilepsy. Thechildren surveyed for this paper were all taking cannabis that waspurported to contain CBD in a high concentration although the amount ofCBD present and the other constituents including THC were not known.Indeed, whilst CBD levels ranged from 0.5 to 28.6 mg/kg/day (in thoseextracts tested), THC levels as high as 0.8 mg/kg/day were reported.

Providing children with TRE with a cannabis extract that comprises THC,which has been described as a pro-convulsant (Consroe et al., 1977), ineven small amounts, let alone at a potentially psychoactive dose of 0.8mg/kg/day, is extremely dangerous and as such there is a real need todetermine whether CBD is in fact efficacious.

To date there have been no controlled trials of CBD in children andyoung adults with TRE.

BRIEF SUMMARY OF THE DISCLOSURE

In accordance with a first aspect of the present invention there isprovided cannabidiol (CBD) for use in the treatment oftreatment-resistant epilepsy (TRE), wherein the epilepsy is febrileinfection related epilepsy syndrome (FIRES).

In accordance with a second aspect of the present invention there isprovided cannabidiol (CBD) for use in the treatment of epilepsy, whereinthe epilepsy is a treatment-resistant epilepsy (TRE), and wherein theCBD is present in an amount that reduces total convulsive seizurefrequency by greater than 50% with respect to the seizure frequencyachieved on concomitant anti-epileptic drugs (AED).

Preferably the CBD is used in combination with two or more concomitantanti-epileptic drugs (AED). The CBD may be formulated for administrationseparately, sequentially or simultaneously with one or more AED or thecombination may be provided in a single dosage form.

Preferably the seizure type to be treated is a complex partial seizure(focal seizure with impairment).

Preferably the CBD is present in an amount that reduces total convulsiveseizure frequency by greater than 70% with respect to the seizurefrequency achieved on concomitant anti-epileptic drugs (AED). Morepreferably the CBD is present in an amount that reduces total convulsiveseizure frequency by greater than 90% with respect to the seizurefrequency achieved on concomitant anti-epileptic drugs (AED). Morepreferably still the CBD is present in an amount that reduces totalconvulsive seizure frequency by 100% with respect to the seizurefrequency achieved on concomitant anti-epileptic drugs (AED).

In one embodiment the CBD is present as a highly purified extract ofcannabis which comprises at least 98% (w/w) CBD.

The one or more AED is preferably selected from the group consisting of:clobazam; levetiracetam; topiramate; stiripentol; phenobarbital;lacsamide; valproic acid; zonisamide; perampanel; and fosphenytoin.

Preferably the CBD is used in combination with clobazam.

Preferably the number of different anti-epileptic drugs or the dose ofAED that are used in combination with the CBD is reduced. Morepreferably the dose of AED which is reduced is of clobazam.

Preferably the dose of CBD is greater than 5 mg/kg/day. Thus for a 15 kgpatient a dose of greater than 75 mg of CBD per day would be provided.Doses greater than 5 mg/kg/day such as greater than 10 mg/kg/day,greater than 15 mg/kg/day, greater than 20 mg/kg/day and greater than 25mg/kg/day are also envisaged to be effective.

In accordance with a third aspect of the present invention there isprovided a method of treating treatment-resistant epilepsy comprisingadministering cannabidiol (CBD) to a subject, wherein the epilepsy isfebrile infection related epilepsy syndrome (FIRES).

In accordance with a fourth aspect of the present invention there isprovided a method of treating treatment-resistant epilepsy comprisingadministering cannabidiol (CBD) to a subject in an amount sufficient toreduce total convulsive seizure frequency by greater than 50% withrespect to the seizure frequency achieved on one or more concomitantanti-epileptic drugs (AED).

DEFINITIONS

Definitions of some of the terms used to describe the invention aredetailed below:

The cannabinoids described in the present application are listed belowalong with their standard abbreviations.

CBD Cannabidiol

CBDA Cannabidiolic acid

CBDV Cannabidivarin

THC Tetrahydro- cannabinol

The table above is not exhaustive and merely details the cannabinoidswhich are identified in the present application for reference. So farover 60 different cannabinoids have been identified and thesecannabinoids can be split into different groups as follows:Phytocannabinoids; Endocannabinoids and Synthetic cannabinoids (whichmay be novel cannabinoids or synthetically produced phytocannabinoids orendocannabinoids).

“Phytocannabinoids” are cannabinoids that originate from nature and canbe found in the cannabis plant. The phytocannabinoids can be isolatedfrom plants to produce a highly purified extract or can be reproducedsynthetically.

“Highly purified cannabinoids” are defined as cannabinoids that havebeen extracted from the cannabis plant and purified to the extent thatother cannabinoids and non-cannabinoid components that are co-extractedwith the cannabinoids have been removed, such that the highly purifiedcannabinoid is greater than or equal to 98% (w/w) pure.

“Synthetic cannabinoids” are compounds that have a cannabinoid orcannabinoid-like structure and are manufactured using chemical meansrather than by the plant.

Phytocannabinoids can be obtained as either the neutral (decarboxylatedform) or the carboxylic acid form depending on the method used toextract the cannabinoids. For example it is known that heating thecarboxylic acid form will cause most of the carboxylic acid form todecarboxylate into the neutral form.

“Treatment-resistant epilepsy” (TRE) is defined as per the ILAE guidanceof 2009 as epilepsy that is not adequately controlled by trials of oneor more AED.

“Childhood epilepsy” refers to the many different syndromes and geneticmutations that can occur to cause epilepsy in childhood. Examples ofsome of these are as follows: Dravet Syndrome; Myoclonic-AbsenceEpilepsy; Lennox-Gastaut syndrome; Generalized Epilepsy of unknownorigin; CDKL5 mutation; Aicardi syndrome; bilateral polymicrogyria;Dup15q; SNAP25; and febrile infection related epilepsy syndrome (FIRES);benign rolandic epilepsy; juvenile myoclonic epilepsy; infantile spasm(West syndrome); and Landau-Kleffner syndrome. The list above isnon-exhaustive as many different childhood epilepsies exist.

DETAILED DESCRIPTION

Preparation of Highly Purified CBD Extract

The following describes the production of the highly-purified (>98% w/w)cannabidiol extract which has a known and constant composition which wasused for the expanded access trials described in Examples below.

In summary the drug substance used in the trials is a liquid carbondioxide extract of high-CBD containing chemotypes of Cannabis sativa L.which had been further purified by a solvent crystallization method toyield CBD. The crystallisation process specifically removes othercannabinoids and plant components to yield greater than 98% CBD.

The Cannabis sativa L. plants are grown, harvested, and processed toproduce a botanical extract (intermediate) and then purified bycrystallization to yield the CBD (drug substance).

The plant starting material is referred to as Botanical Raw Material(BRM); the botanical extract is the intermediate; and the activepharmaceutical ingredient (API) is CBD, the drug substance.

Both the botanical starting material and the botanical extract arecontrolled by specifications. The drug substance specification isdescribed in Table 1 below.

TABLE 1 CBD Specification Test Test Method Limits Appearance VisualOff-white/pale yellow crystals Identification A HPLC-UV Retention timeof major peak corresponds to certified CBD Reference StandardIdentification B GC-FID/MS Retention time and mass spectrum of majorpeak corresponds to certified CBD Reference Standard Identification CFT-IR Conforms to reference spectrum for certified CBD ReferenceStandard Identification D Melting Point 65-67° C. Identification ESpecific Optical Conforms with certified CBD Rotation ReferenceStandard; −110° to −140° (in 95% ethanol) Total Purity Calculation≥98.0% Chromatographic Purity 1 HPLC-UV ≥98.0% Chromatographic Purity 2GC-FID/MS ≥98.0% Impurities (Other HPLC-UV Cannabinoids): CBDA NMT 0.15%w/w CBDV NMT 1.0% w/w Δ⁹ THC NMT 0.15% w/w CBD-C4 NMT 0.5% w/w ResidualSolvents: GC Alkane NMT 0.5% w/w Ethanol NMT 0.5% w/w Residual WaterKarl Fischer NMT 1.0% w/w NMT- Not more than

The purity of the CBD drug substance achieved is greater than 98%. Thepossible impurities are related cannabinoids: CBDA, CBDV, CBD-C4 andTHC.

Distinct chemotypes of Cannabis sativa L. plant have been produced tomaximize the output of the specific chemical constituents, thecannabinoids. One type of plant produces predominantly CBD. Only the(−)-trans isomer occurs naturally, furthermore during purification thestereochemistry of CBD is not affected.

Production of the Intermediate

An overview of the steps to produce a botanical extract, theintermediate, are as follows:

-   1. Growing-   2. Decarboxylation-   3. Extraction No.1—using liquid CO₂-   4. Extraction No.2—‘winterization’ using ethanol-   5. Filtration-   6. Evaporation

High CBD chemovars were grown, harvested and dried and stored in a dryroom until required. The botanical raw material (BRM) was finely choppedusing an Apex mill fitted with a 1 mm screen. The milled BRM was storedin a freezer for up to 3 months prior to extraction.

Decarboxylation of CBDA to CBD was carried out using a large Heraeustray oven. The decarboxylation batch size in the Heraeus isapproximately 15 Kg. Trays were placed in the oven and heated to 105°C.; the BRM took 96.25 minutes to reach 105° C. Held at 105° C. for 15Minutes. Oven then set to 150° C.; the BRM took 75.7 minutes to reach150° C.; BRM held at 150° C. for 130 Minutes. Total time in the oven was380 Minutes, including 45 minutes cooling and 15 Minutes venting.

Extraction No 1 was performed using liquid CO₂ at 60 bar/10° C. toproduce botanical drug substance (BDS) which was used forcrystallisation to produce the test material.

The crude CBD BDS was winterised in Extraction No 2 under standardconditions (2 volumes of ethanol at minus 20° C. for around 50 hours).The precipitated waxes were removed by filtration and the solventevaporated using the rotary evaporator (water bath up to 60° C.) toyield the BDS.

Production of the Drug Substance

The manufacturing steps to produce the drug substance from theintermediate botanical extract are as follows:

-   1. Crystallization using C5-C12 straight chain or branched alkane-   2. Filtration-   3. Optional recrystallization from C5-C12 straight chain or branched    alkane-   4. Vacuum drying

Intermediate botanical extract (12kg) produced using the methodologyabove was dispersed in C5-C12 straight chain or branched alkane (9000ml, 0.75 vols) in a 30 liter stainless steel vessel.

The mixture was manually agitated to break up any lumps and the sealedcontainer then placed in a freezer for approximately 48 hours.

The crystals were isolated by vacuum filtration, washed with aliquots ofcold C5-C12 straight chain or branched alkane (total 12000 ml), anddried under a vacuum of <10 mb at a temperature of 60° C. until drybefore submitting the drug substance for analysis.

The dried product was stored in a freezer at minus 20° C. in apharmaceutical grade stainless steel container, with FDA food gradeapproved silicone seal and clamps.

Examples 1 to 3 below describe the use of a highly purified cannabisextract comprising cannabidiol (CBD). Cannabidiol is the most abundantnon-psychoactive cannabinoid in the cannabis plant. Previous studies inanimals have demonstrated that CBD has anticonvulsant efficacy inmultiple species and models.

Example 1 describes data produced in an expanded access treatmentprogram in children with TRE.

Examples 2 to 4 demonstrates the efficacy of CBD in children with Dravetsyndrome, myoclonic absence seizures and FIRES respectively.

EXAMPLE 1 Efficacy of Cannabidiol in Children and Young Adults withTreatment-Resistant Epilepsy

Materials and Methods

Twenty-seven children and young adults with severe, childhood onsettreatment-resistant epilepsy (TRE) were tested with a highly purifiedextract of cannabidiol (CBD) obtained from a cannabis plant. Theparticipants in the study were part of an expanded access compassionateuse program for CBD.

All patients entered a baseline period of 4 weeks whenparents/caregivers kept prospective seizure diaries, noting allcountable motor seizure types.

The patients then received a highly purified CBD extract (greater than98% CBD w/w) in sesame oil, of known and constant composition, at a doseof 5 mg/kg/day in addition to their baseline anti-epileptic drug (AED)regimen.

The daily dose was gradually increased by 2 to 5 mg/kg increments untilintolerance occurred or a maximum dose of 25 mg/kg/day was achieved.

Patients were seen at regular intervals of 2-4 weeks. Laboratory testingfor hematologic, liver, kidney function, and concomitant AED levels wasperformed at baseline, and after 4, 8 and 12 weeks of CBD therapy.

Results

There were 27 children and young adult patients who received at least 3months of treatment all of whom suffered from treatment-resistantepilepsy.

All patients were taking at least two concomitant anti-epileptic drugs.These included clobazam; levetiracetam; topiramate; stiripentol;phenobarbital; lacsamide; valproic acid; zonisamide. The average numberof concomitant antiepileptic drugs being taken was 2.7. The majoritytook either clobazam and/or valproic acid.

Co-treatment of CBD with clobazam was a significant predictor of apositive treatment response of greater than 50% responder rate. Therewas an odds ratio (OR) of 3.3 for total seizure reduction and of 1.9 forconvulsive seizures. The OR evaluates whether the odds of a certainevent or outcome is the same for two groups. Specifically, the ORmeasures the ratio of the odds that an event or result will occur to theodds of the event not happening. An OR greater than 1 signifies thatpatients treated with a combination of CBD with clobazam will have abetter odds of having a positive reduction in seizures than if they werenot taking this combination of medications.

The median number of seizures that these patients suffered from beforestarting treatment was 30 seizures per month, with a range of 4 to 2,800seizures per month being recorded.

Efficacy results for the 27 patients are summarized in Table 2 below.

TABLE 2 Changes in Seizure Frequency with CBD Therapy Month 3 Allpatients (n = 27) Responder rate (>50% reduction) [%] 13 [48%] Responderrate (>70% reduction) [%] 11 [41%] Responder rate (>90% reduction) [%] 6[22%] Seizure free [%] 2 [7%]

Table 2 shows that after 3 months of therapy, 48% of patients had anequal to or greater than >50% reduction in seizures.

Remarkably, two of the patients, equating to 7%, were entirely free fromseizures at the three month stage.

None of the 27 subjects withdrew during the 3-month treatment period andadverse events were mild and well tolerated. Common adverse eventsincluded somnolence, fatigue, decreased appetite, increased appetite anddiarrhoea.

In five subjects their dose of clobazam was reduced due to its sedativeeffect.

Conclusions

These preliminary results indicate that CBD significantly reduces thenumber of seizures in a high proportion of patients that do not respondwell to existing AED. The cannabidiol was generally well-tolerated indoses up to 25 mg/kg/day.

It was surprising that in this group of patients which aretreatment-resistant such a high number were able to gain an effect. Thefact that nearly half of the patients (48%) benefitted from at least afifty percent reduction in the number of seizures that they sufferedfrom was remarkable.

Furthermore, nearly a quarter (22%) of patients whose seizures were notcontrolled with at least two anti-epileptic drugs, experienced areduction of 90% of the number of seizures they were experiencing and 7%were completely seizure free at the end of the 3 month trial period.

Even more remarkable were the results for some defined sub-sets of thisgeneric group and these are set out on Examples 2 to 4 below.

EXAMPLE 2 Efficacy of Cannabidiol in Children and Young Adults withTreatment Resistant Dravet Syndrome

Materials and Methods

Nine children and young adults with treatment-resistant Dravet syndromewere part of an expanded access compassionate use program for highlypurified CBD extract as described in Example 1.

Results

All nine patients with Dravet syndrome were taking at least twoconcomitant anti-epileptic drugs. These were largely AED operating viaGABA and included clobazam; levetiracetam; topiramate; stiripentol;phenobarbital; lacsamide; valproic acid; and zonisamide. The averagenumber of concomitant antiepileptic drugs being taken was 2.7.

The mean number of seizures that these patients suffered from beforestarting treatment was 35 seizures per month, with a range of 6 to 112seizures per month recorded.

Efficacy results for the 9 patients are summarized in Table 3 below.

TABLE 3 Changes in Seizure Frequency with CBD Therapy in Dravet Syndromepatients All patients excluding Dravet All Dravet patients patientspatients (n = 9) (n = 27) (n = 18) Responder rate (>50% 5 [56%] 13 [48%]8 [44%] reduction) [%] Responder rate (>70% 4 [44%] 11 [41%] 7 [39%]reduction) [%] Responder rate (>90% 3 [33%] 6 [22%] 3 [17%] reduction)[%] Seizure free [%] 2 [22%] 2 [7%] 0

Table 3 shows that after 3 months of therapy, 56% of patients had anequal to or greater than 50% reduction in seizures, a third had a 90%reduction and remarkably 22%, were entirely free from seizures at thethree month stage.

None of the 9 subjects withdrew during the 3-month treatment period andadverse events were mild and well tolerated. Common adverse eventsincluded somnolence, fatigue, decreased appetite, increased appetite anddiarrhoea.

Conclusions

These data demonstrate that in this sub-group of patients withtreatment-resistant

Dravet syndrome a surprisingly high number were able to gain a dramaticreduction in the number of seizures.

Nearly a quarter (22%) of patients were entirely seizure free at the endof the 3 month trial period. This would not be expected in this group ofpatients who were taking a large number of different anti-epilepticmedications and yet were still suffering from a large number of seizuresper day.

EXAMPLE 3 Efficacy of Cannabidiol in Children and Young Adults withTreatment Resistant Myoclonic Absence Seizures

Materials and Methods

Four children and young adults with treatment-resistant myoclonicabsence seizures were part of an expanded access compassionate useprogram for highly purified CBD extract as described in Example 1.

Results

All four patients with myoclonic absence seizures were taking at leasttwo concomitant anti-epileptic drugs. These were largely AED operatingvia GABA and included clobazam; levetiracetam; topiramate; stiripentol;phenobarbital; lacsamide; valproic acid; and zonisamide. The averagenumber of concomitant antiepileptic drugs being taken was 2.7.

Efficacy results for the four patients are summarized in Table 4 below.

TABLE 4 Changes in Seizure Frequency with CBD Therapy in patients withmyoclonic absence seizures (MAS) All patients MAS All excluding patientspatients MAS patients (n = 4) (n = 27) (n = 23) Responder rate (>50% 2[50%] 13 [48%] 11 [48%] reduction) [%] Responder rate (>70% 2 [50%] 11[41%] 9 [39%] reduction) [%] Responder rate (>90% 1 [25%] 6 [22%] 5[22%] reduction) [%] Seizure free [%] 0 2 [7%] 2 [9%]

Table 4 shows that after 3 months of therapy, half of the patients hadan equal to or greater than 50% reduction in seizures, one patient (25%)had a 90% reduction at the three month stage.

None of the 4 subjects withdrew during the 3-month treatment period andadverse events were mild and well tolerated. Common adverse eventsincluded somnolence, fatigue, decreased appetite, increased appetite anddiarrhoea.

Conclusions

These data demonstrate that in this sub-group of patients withtreatment-resistant MAS a surprisingly high number were able to gain areduction in the number of seizures.

EXAMPLE 4 Efficacy of Cannabidiol in Children with Treatment ResistantFebrile Infection Related Epilepy Syndrome (FIRES)

Febrile Infection Related Epilepsy Syndrome (FIRES) is a catastrophicepileptic encephalopathy with an unidentified aetiology that comprises asmall minority of all patients with refractory status epilepticus.

This syndrome occurs in previously healthy children with 66-100% ofsurvivors becoming developmentally disabled. The mortality rate is up to30%. There is a critical need for new therapies to treat this condition.

Materials and Methods

Three patients with FIRES, with an age range of from 4 to 15 years, weretreated with CBD under an expanded access program as describedpreviously in Example 1.

Safety laboratory studies, physical/neurological exams, 24 hourvideo/EEG and seizure types and frequencies were assessed at baselineand one month after starting CBD.

A highly purified extract of CBD as an oral solution in sesame oil wasused at a concentration of 25 mg/mL.

Treatment was initiated at a dose of 10 mg/kg/day given in two divideddoses, increasing by 5 mg/kg/day every 3 days.

Following seizure improvement an average of 2 AEDs were weaned.

Results

Prior to initiation of treatment with highly purified CBD, the patientsall suffered from refractory seizures or status epilepticus. These hadbeen treated with anaesthetics including midazolam infusion,pentobarbital infusion, propofol infusion, and isofluorane infusion,additionally patients also were given steroids including lidocaineinfusion, and methylprednisolone and other treatments includingketamine, fosphenytoin, thiamine, rituximab, cyclophosphamide,intravenous immunoglobulin, and a hypothermia protocol.

At the time of initiation of CBD, the patients were taking between threeand five anti-epileptic drugs including: levetiracetam, clobazam,perampanel, phenobarbital, phenytoin, carbamezapine, felbamate,ketogenic diet, lamotrigine, valproic acid and vagus nerve stimulationtherapy.

Baseline 24 hour EEG of seizures were recorded. The total seizures atbaseline and during the treatment period are shown in Table 5. Patient 1was shown to be seizure free after starting treatment for almost all ofthe treatment period, with the number of seizures being reduced from 7to 0.3 over a 24 week period. Patient 2 had a 50% reduction in seizuresafter 4 weeks however the seizure frequency increased after a further 4weeks then started to decrease again after 16 weeks of treatment. Themost remarkable response was seen in Patient 3, who suffered from 5600seizures at baseline. The number of seizures were dramatically reducedafter 4 weeks and at week 24 this patient was still demonstrating agreater than 90% reduction in the number of seizures.

The type of seizures that occurred in the three FIRES patients were allcomplex partial seizures (focal seizures with impairment). None of theFIRES patients suffered from focal seizures with secondarygeneralisation or convulsive seizures.

TABLE 5 Total Seizure Data Frequency Change % Change Responder ResponderResponder (per from from (>=50% (>=70% (>=90% Seizure Visit month)Baseline Baseline Reduction) Reduction) Reduction) Free Patient 1 BL 4.0n/a n/a n/a n/a n/a n/a Wk 4 0.0 −4.0 −100.0 Yes Yes Yes Yes Wk 8 1.0−3.0 −75.0 Yes Yes No No Wk 12 0.0 −4.0 −100.0 Yes Yes Yes Yes Wk 16 0.0−4.0 −100.0 Yes Yes Yes Yes Wk 24 0.3 −3.7 −92.0 Yes Yes Yes No Patient2 BL 7.0 n/a n/a n/a n/a n/a n/a Wk 2 0.8 −6.2 −88.6 Yes Yes No No Wk 43.0 −4.0 −57.1 Yes No No No Wk 8 10.0 3.0 42.9 No No No No Wk 12 8.0 1.014.3 No No No No Wk 16 4.0 −3.0 −42.9 No No No No Patient 3 BL 5600.0n/a n/a n/a n/a n/a n/a Wk 4 47.2 −5552.8 −99.2 Yes Yes Yes No Wk 8 9.2−5590.8 −99.8 Yes Yes Yes No Wk 12 141.6 −5458.4 −97.5 Yes Yes Yes No Wk24 542.0 −5058.0 −90.3 Yes Yes Yes No

Follow up laboratory tests showed no changes in safety studies orconcomitant AED levels. No treatment related adverse effects wereobserved.

Conclusions

CBD treatment was very well tolerated and associated with a dramatic andnearly immediate greater than 90% improvement in clinical andelectrographic seizure burden in two of the three children withrefractory seizures or status epilepticus due to FIRES.

After a reduction in seizures the patients were able to walk andverbalise once more.

SUMMARY TABLE AND CONCLUSIONS

Table 6 below summarises the data obtained in the three sub-sets: Dravetsyndrome; myoclonic absence seizures (MAS) and febrile infection relatedepilepsy syndrome (FIRES) after 12 weeks of treatment which have beendescribed in the Examples 2 to 4 above. In addition the data for theremainder of the patients with other epilepsy syndromes are detailed.These data which exclude the patients with Dravet, MAS and FIRES show afar lower responder rate than for the specified sub-sets of the abovespecified sub-sets of epilepsy.

In particular, the responder rate for patients obtaining a greater than90% reduction in their seizures is reduced from 33% in Dravet patientsto only 8% in the unspecified group. This suggests that patientssuffering from a TRE of sub-type Dravet syndrome, myoclonic absenceseizures or FIRES will respond better to treatment with highly purifiedCBD than patients with other epilepsy sub-types.

TABLE 6 Changes in Seizure Frequency with CBD Therapy in patients withsub-type TRE and all patients excluding the sub-types. All patients(excluding Dravet, MAS Dravet MAS FIRES and FIRES) patients patientspatients (n = 13) (n = 9) (n = 4) (n = 3) Responder rate (>50% 5 [38%] 5[56%] 2 [50%] 2 [67%] reduction) [%] Responder rate (>70% 4 [31%] 4[44%] 2 [50%] 2 [67%] reduction) [%] Responder rate (>90% 1 [8%] 3 [33%]1 [25%] 2 [67%] reduction) [%] Seizure free [%] 0 2 [22%] 0 1 [33%]

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The invention claimed is:
 1. A method of reducing convulsive seizurefrequency in a patient with a treatment-resistant epilepsy, which isDravet syndrome, comprising administering to the patient in need thereofcannabidiol (CBD), wherein the CBD has a purity of at least 98% (w/w)CBD and comprises not more than 0.15% (w/w) Δ9-tetrahydrocannabinol(THC); and wherein dose of the CBD is at least 15 mg/kg/day.
 2. A methodof reducing convulsive seizure frequency in a patient with atreatment-resistant epilepsy, which is Dravet syndrome, comprisingadministering to the patient in need thereof cannabidiol (CBD), whereinthe CBD has a purity of at least 98% (w/w) CBD and comprises not morethan 0.15% (w/w) Δ9-tetrahydrocannabinol (THC), wherein the dose of theCBD is at least 10 mg/kg/day.
 3. The method of claim 2, wherein the doseof the CBD is 10 mg/kg/day.
 4. The method of claim 2, wherein the doseof the CBD is 12 mg/kg/day.
 5. The method of claim 2, wherein the doseof the CBD is 14 mg/kg/day.
 6. The method of claim 2, wherein the doseof the CBD is 15 mg/kg/day.
 7. The method of claim 2, wherein the doseof the CBD is 16 mg/kg/day.
 8. The method of claim 2, wherein the doseof the CBD is 18 mg/kg/day.
 9. The method of claim 2, wherein the doseof the CBD is 20 mg/kg/day.
 10. A method of treating convulsive seizuresin a patient with a treatment-resistant epilepsy, which is Dravetsyndrome, comprising administering to the patient in need thereofcannabidiol (CBD), wherein the CBD has a purity of at least 98% (w/w)CBD and comprises not more than 0.15% (w/w) Δ9-tetrahydrocannabinol(THC); and wherein dose of the CBD is at least 15 mg/kg/day.
 11. Amethod of treating convulsive seizures in a patient with atreatment-resistant epilepsy, which is Dravet syndrome, comprisingadministering to the patient in need thereof cannabidiol (CBD), whereinthe CBD has a purity of at least 98% (w/w) CBD and comprises not morethan 0.15% (w/w) Δ9-tetrahydrocannabinol (THC), wherein the dose of theCBD is at least 10 mg/kg/day.